How do you stop bad cat behavior?

My cats are around eight years old. They have always been indoor cats, so I had their claws removed due to furniture issues. Anyhow, in the past month, both my cats have been using the bathroom in front of the kitty litter on the carpet. WHY? They have never done this before, and my husband already doesn’t like having animals in the house. What do I do?? I love them way too much to ever part with them.